Solve the problem. The attending physician in an emergency room treats an unconscious patient suspected of a drug overdose. The physician does not know the initial concentration Ao of the drug in the bloodstream at the time of injection. However, the physician knows that after 3 hr. the drug concentration in the blood is 0.75 ug/dL and after 4 hr. the concentration is 0.719 ug/dL. The modelA(t) = Ao eth represents the drug concentration A(t) in ugldL in the bloodstream t hours after injection. The value of k is a constant related to the rate at which the drug is removed by the body. Select one: O a. a. 0.75 = Age3k b.0.719 = Anek c. k = 0.618 O b. a. 0.75 = Ape-3k b. 0.719 = Age-4k c. k = 0.042 O c. a. 0.75 = Age-3k b. 0.719 = Age-4k c. k = 0.618 O d. a. 0.75 = Age3k b. 0.719 = Apetk c.k = 0.042